In a phone interview with KCRA 3, former California Highway Patrol accident investigator Bob Snook said the Lodi Police Department has likely taken the vehicles involved to a warehouse to perform a "car autopsy."

He said that involves disassembling each vehicle to verify if its brakes and other vital functions were working properly.

Snook said most vehicles equipped with air bags are also equipped with "black box" data recorders that track a vehicle's speed, accelerator and brake use during the seconds before a collision.

He said investigators likely will obtain subpoenas from cellphone companies to know which drivers might have been talking on their phone at the time of the crash.

A police officer returned to the intersection of Ham Lane and Vine Street on Thursday evening.

He said he was taking photographs to show the angle of the sun at the time of the crash.

A Lodi police spokesman said Thursday investigators have received two search warrants, one for an undisclosed address and the other for a person.

Snook said a search warrant for a person can sometimes be used to obtain a blood sample for alcohol and drug testing, but is more likely to take a personal possession, such as a cellphone or briefcase.

Several witnesses have reported seeing a 2002 GMC SUV speeding down Ham Lane with its driver on a cellphone Tuesday evening, just before the crash.

That vehicle ended up a few hundred feet beyond the point of impact, near a bus stop in front of Lodi Middle School.

Six members of the Miranda family, including an unborn child, were riding in a white pickup truck and killed.

The Mirandas' 9-year-old son survived.

According to public records, that vehicle is registered to a man who lives about a mile from the crash site.

No one answered the door Wednesday at the home.

Reached by phone, a man who said he was a relative declined to comment.

A woman who said she was the daughter of the vehicle's owner told KCRA 3 her father is in his 70s and has been unable to drive recently because he has been in a hospital.

Neighbors reported seeing a couple who had been living in the home and taking care of the man.

Neighbors remember a tan SUV sometimes parked at the residence, but have not seen it since before the crash.

Snook said it is not unusual for investigators to take time before identifying a suspect.

He said such a complicated case could last for months before investigators can determine if someone is at fault.

The city of Lodi does not use red-light cameras.

Police have said they plan to ask nearby residents and businesses if they have surveillance video from the night of the crash.

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